Architectural trim components are traditionally constructed from wood. Unfortunately, wood is susceptible to decay, and the most common wood decay is dry rot. Dry rot is caused by certain fungi which grow when sufficient moisture is present, allowing the fungi to grow and digest the wood, causing the wood to shrink, show a brown discoloration, and crack into pieces. There are many species of fungi that can cause dry rot. For instance, fungus such as serpula lacrymans, armillaria, or lignicolous can cause dry rot wood decay. Some fungi secrete an enzyme that breaks down cellulose in wood, which can also lead to discoloration and cracking known as soft rot. These include fungus such as chaetomium, ceratocystis and kretzschmaria deusta fungi. White rot fungi, common in hardwoods used outdoors, breaks down lignin in wood, leaving lighter colored cellulose behind.
Plastics, including composites made of plastic and wood, have been recognized as a substitute for architectural trim structures. Plastic has weather resistant qualities, can be treated to resist ultraviolet radiation, and has a surface porosity that accepts painting. However, simply substituting plastic for a wood trim structure is not as desirable since plastic possesses poor structural capabilities. Further, a large chunk of plastic creates both a weight and a cost disadvantage. And, while plastic may be a beneficial substitute for small trim components, the trend has been to develop lighter, stronger, and more durable products.
Heating plastic to form curves and bends is well known, but includes the inherent problems caused by the heat changing the structure of the plastic. Fiber reinforced thermoset plastics, such as fiberglass, also provide desirable weather resistant performance qualities, but lack the look and feel of traditional wood trim components. Further, fiber reinforced plastics are difficult to shape, modify, or otherwise work with in the field.
What is lacking in the art are architectural trim components, and the method of constructing them, that can substitute for wood architectural trim components. The components should be constructed of plastic or a composite of plastic and wood, the preferable material being cellular polyvinylchloride, to produce trim components that are light weight, easily manufactured and installed, and are imperious to weather.